Fluid-expansion rubber to be used on swabs, agitators, and packers for oil wells



Patented May 18, 1926.

UNITED STATES PATENT OFFICE.

WALTER G. BISBEE AND BEN P. HOFFMAN, OF BRISTOW, OKLAHOMA.

FLUID-EXPANSION RUBBER TO BE USED ON SWABS, AGITATORS, AND IPACKERS FOR OIL WELLS.

Application filed June 13, 1924. Serial No. 719 872.

This invention rclates to improvenents in rubbers for packers, swabs, agitators and similar apparatus utilized in the drilling and operation of deep weils.

The invention relates toiinprovenents in rubber for swabs, agitators, and packers, in'

which the weight and pressure ot the fluid expands the rubber to fit the casing or pipo, when the swab is being withdrawn from the well, or when the swab is being used as an agitator and is on the upward sti-oke, or when the rubber is inverted to serve as a packer. By reason of the peculiar Construction of the rubber, it climinates all friction and vaeuum when being lowered into the well or pipe, as the sides of the rubber do not come in contact with the walls of pipe or casing. v

Other objects and features will more clearly hereinat'ter appear by reference to the 'accompanying drawing forming a part of this specification and wherein like numerals of reference designate corresponding parts throughout the several views, in which:

Figure 1 is a side elevation With the cap removed and part being in section;

Figure 2 is a top plan view;

Figure 3 is a View of the cap similar to Fig. 1;

Figure 4 is a top plan of the cap; and

Figure 5 is a side elevation of the assembled device partly in section.

In the present embodiment, the packer body is shown to conp'ise an integral tubur lar structure of suitable rubber composition.

The body is formed with an annular chamber A which extends from the upper end down- Wardly to a point near the lower end. This chamber A partitions the greater portion of the body into inner wall section B and the euter wall section C, the latter being reduced for a portion of its length to form shoulder 0.

A cap is provided for the upper eXt-remity of'the paekef and functions both as a guard for the outer surface of the rubber and also as a spacer and fluid feed for the chamber A. This cap includes downwardly extending inner 'and outer spaced. flanges E and F, the outer flange E being adapted to enclose the upper end of the rubber and seat against the s oulder c. The. diameter of this flange is such as to be substantially flush with the outer diameter of the rubber or to extend slightly beyond the latter to form ,a protection therefor against frictional engagenent with the casing; The inner fiange F as shown in Figurc '5 is adapted to be postioncd between inner and outer Walls B and (l to space the latter. This flange is provided with a plurality ot ports orpassages (i torning a communication between the chamber and the atmosphere, therehy enabling the entrance and exit ot' fluid froni.

the chamber to cause the expansion and contraction of the outcr wall as may be desircd. The cap body is formed with a central opening corresponding in diameter to the passage through the tubular body of the rubber.

When the present device is used as a swab in connection with oil wells, the open end of the chamber will be turned upward to enable the fluid to gain access thei-eto. The weight of the fluid entering through the ports in the flange F will cause the e'xpansi'on of the outer wall ot' the rubber and the engagenient of the latter with the wall of the well. This rubber is also utilized in the upward position when Operating as an agitator, the upward stroke of the device causing the fluid to expand and engage the Wall. v When utilizcd as a packer, the open end ofthe expansion chamber is directed downwardly to permit the fluid pressure in the well to act against the chamber walls. The Construction of the rubber itself and the cap therefore is such as to eliminate the friction movement in a well casing, the outer annular flange E of the cap being of suflici'ent dir ameter to prevent the engagement of the outer surface of the packer With the inner surface of the wall during non-working stroke of the device.

Having thus described our invention, what weelain' as new and desire to secure by Letters Patent is:

LA paeker comprising a cylndrical flexible body fdrmed with an annular chamber, and a cap for said packer having an inner annular flange formed with passages to permit communication with said chamber, said cap also having an outer annular flange encircling one end portion of the cylindrical body.

2. In a device of the class described, a tubular flexible body formcd with an annular chamber within its wall, said chamber being closed at one end and open at the other end,

a cap for said body formed with an annuiar extension adapted to normally seat in the upper end`of said chamber and space the walls thereof, said extension being formed with a plurality of epassages for efl'ecting communication between said chamber and the atmosphere, and an annular flange on the cap encircling and confinng one end portion of the tubular body. v

3. In a device of the class described, a tubular flexible packer formed with a concentric annuiar expansion chamber within its wall, and having an externally reduced upper extremity, a cap for said paeker having an annular outer wall seatin on the i'educed portion and being provide with ports arranged to communicate with said chamber 4. In a device of the class described, a tubular body ^comprsing inner and outer spaced walls forming an expansion chamber, a cap having an outer flange engagin the outer face of said outer wail, an inner an seated between said inner and outer wal s, and ports formed in said inner flange for eflecting communication between said chamber and the atmosphere.

WALTER G. BISBEE.

,BEN P. HOFFMAN. 

